Long strings of numbers like this are the standard naming format for files uploaded to Discord . If you found this in a folder or received it in a chat, it was likely hosted on Discord's servers.
Usually no. It won't harm your computer, but it might close your Discord or Instagram app.
If you have downloaded this file and are unsure of its contents:
In the past, numeric filenames like this were used for These files used specific encoding tricks (like an impossible aspect ratio or frame rate) to make a user's app restart when they viewed it.
Open the file in a browser window (drag and drop into Chrome or Firefox) rather than a system-level media player. This provides a layer of isolation.